x-Risk Course
Open access · Self-paced

Module 1 / Lesson 1.1

Describing Risks

1 min readVideo included

Let’s begin with the foundation: What exactly is a risk? Throughout this course, we use a simple and practical definition:

Learning guide

  • Learning: Learn the three dimensions of risk: frequency, severity, and scope.
  • Reflection: Think of a real risk you face (e.g., driving). How would you rate its frequency, severity, and scope?
Risk refers to the possibility of a bad outcome that might or might not happen in the future.

Risks exist everywhere, from slipping on ice to global pandemics. To better understand risk, we use three key dimensions:

Frequency (Likelihood)

  • How often might the outcome happen?
  • Is it common or rare?
  • Can be described using probabilities or time intervals.

Severity (Impact)

  • How harmful is the outcome if it occurs?
  • Minor inconvenience, moderate harm, or catastrophic damage?

Scope (Who is affected?)

  • Who would be impacted? Just you, or many people?
  • Some risks are personal; others are global.

Video Explanation

Please watch this short video describing the ideas about risk above:


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x-Risk Course · Existential Risk: An Open Course

Designed and led by Professor Stephen H. Shore. Online contributors: Abbad Ali and Suyog Thengale.

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Original course materials © Stephen H. Shore · CC BY-NC 4.0. Third-party materials retain their own terms.

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